Research On Anode Performance Of Urine-powered Microbial Fuel Cell

Microbial fuel cell can produce electricity by using organic pollutants as fuels.Meanwhile,it has a high theoretical utilization efficiency which is not limited by the Carnot cycle efficiency.Thus,it is a pioneering technology growing up in sewage treatment and environmental energy field in recent years.Microbial fuel cell which recovers energy from urine is named as urine-powered microbial fuel cell(UMFC).However,the low power density of UMFC remains one of the main obstacles for their practical applications.The anode electrode undertakes electron collection and exporting.Therefore,the anode which produced electrons by microbial metabolism is the key unit determining the performance of UMFC.Aiming at improving the performance of UMFC anode,changing basement material,chemical oxidation modification and three-dimensional printing preparations were employed in this paper,the main work and results of this dissertation are summarized as followings:(1)Oxidants of nitric acid and acidic potassium dichromate were used to modify carbon cloths(CC)as anodes.Both Nitrate modified anode and Potassium dichromate modified anode were fabricated in this method and they were compared with Carbon cloth anode.It indicated that the amount of surface functional groups was growing by chemical oxidants,which made a great efficiency to MFC performance.The advantage electrogenesis microorganism whose substrate is anolyte was identified by 16 S r DNA amplification sequencing technology,which was ranged in Proteobacteria Deltaproteobacteria Desulfuromonadales Geobacteraceae Geobacter Geobacter_sp._GSS01.(2)Chronopotentiometry was employed to modify CC with graphene(GNS)through electrolytic deposition.The time of electrolytic deposition was selected as 40 s,50 s,60 s and 70 s.Thus,40-GNS/CC,50-GNS/CC,60-GNS/CC and 70-GNS/CC were gained.It indicated that the time of electrolytic deposition would affect performance of UMFC,the best time is 60 s.The advantage electrogenesis microorganism whose substrate is synthetic urine was ranged in Proteobacteria Gammaproteobacteria Enterobacteriales Enterobacteriaceae Enterobacter.(3)Nickel foam anode,Copper foam anode and Iron nickel foam anode were used as UMFC anodes,respectively.Electrochemical testing and energy characterization indicated that Cu-Anode had a good electrochemical performance and the biocompatibility of Fe Ni-Anode was better than Ni-Anode.(4)Three-dimensional printing(3DP)technology was employed to fabricate 316 L stainless steel skeleton anode(3DP-SS)and Titanium alloy skeleton anode(3DP-Ti)both of which were three dimensional(3D)structure cube anodes.Macro-porous 3D anodes of good electrochemical performance for UMFCs were fabricated by 3DP and polyaniline(PANI)surface modification.It indicated that,special anode design for particular reactor can come true with the help of 3DP,which can be difficult to fabricate by conventional methods.Meanwhile,the structure of anodes could be under controlled.PANI could improve the anode performance,thus,the performance of UMFC could also be improved.